Table 5.

Multivariable model of developing chronic opioid use

	Odds Ratio	P > z	95% Confidence Interval
Age categories, y
18–30	Reference
5–17	0.56	<0.01	0.54	0.57
31–50	1.57	<0.01	1.55	1.58
51–65	1.78	<0.01	1.76	1.80
66–99	1.53	<0.01	1.51	1.55
Sex
Male	Reference
Female	1.06	<0.01	1.05	1.07
Missing	1.28	<0.01	1.17	1.41
Payment type
Commercial	Reference
Private pay	1.03	<0.01	1.02	1.05
Medicare	1.12	<0.01	1.11	1.14
Medicaid	1.72	<0.01	1.70	1.74
Workers’ compensation	1.95	<0.01	1.84	2.05
Major medical	3.33	<0.01	3.25	3.42
Extended-release
No	Reference
Yes	1.79	<0.01	1.74	1.84
Month filled
January	Reference
February	0.98	0.03	0.97	1.00
March	0.94	<0.01	0.93	0.96
April	1.04	<0.01	1.02	1.06
May	0.89	<0.01	0.88	0.91
June	0.86	<0.01	0.85	0.88
July	0.84	<0.01	0.83	0.86
August	0.82	<0.01	0.81	0.84
September	0.79	<0.01	0.78	0.81
October	0.75	<0.01	0.74	0.76
November	0.65	<0.01	0.64	0.66
December	0.70	<0.01	0.69	0.71
Year filled
2013	Reference
2014	0.88	<0.01	0.87	0.89
2015	0.60	<0.01	0.60	0.61
2016	0.31	<0.01	0.31	0.32
Prescription morphine milligram equivalents
9–50	Reference
51–100	0.91	<0.01	0.90	0.92
101–150	1.17	<0.01	1.15	1.18
151–200	1.26	<0.01	1.23	1.28
201–250	1.30	<0.01	1.28	1.33
251–300	1.81	<0.01	1.78	1.84
301–350	1.55	<0.01	1.48	1.62
351–400	1.53	<0.01	1.48	1.58
401–450	2.20	<0.01	2.15	2.24
451–500	2.05	<0.01	1.96	2.14
>500	2.90	<0.01	2.85	2.95
Specialty of prescriber
Internal medicine	Reference
Ophthalmology	0.33	<0.01	0.3	0.36
Gynecology	0.37	<0.01	0.36	0.38
Dentistry	0.39	<0.01	0.38	0.4
Specialty surgery	0.44	<0.01	0.43	0.45
Dermatology	0.45	<0.01	0.41	0.5
Radiology	0.49	<0.01	0.45	0.53
Psychiatry	0.54	<0.01	0.5	0.58
Other	0.60	<0.01	0.59	0.61
Missing	0.67	<0.01	0.66	0.67
Orthopedics	0.74	<0.01	0.72	0.75
Pediatrics	0.74	<0.01	0.7	0.78
Hematology/oncology	0.78	<0.01	0.73	0.82
Midlevel	0.84	<0.01	0.82	0.86
Emergency medicine	0.85	<0.01	0.84	0.86
Addiction medicine	1.02	0.91	0.76	1.37
Physical medicine	1.29	<0.01	1.24	1.34
Neurology	1.43	<0.01	1.33	1.54
Anesthesiology	1.46	<0.01	1.42	1.51